<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    div {
      width: 300px;
      height: 300px;
      background-color: pink;
    }

    /* body {
      margin: 0;
    }

    p {
      margin: 0;
    }

    ul {
      list-style: none;
      margin: 0;
      padding: 0;
    } */

    /* blockquote, body, button, dd, dl, dt, fieldset, form, h1, h2, h3, h4, h5, h6, hr, input, legend, li, ol, p, pre, td, textarea, th, ul {
      margin: 0;
      padding: 0;
    } */

    * {
      margin: 0;
      padding: 0;
    }
  </style>
</head>
<body>
  <div></div>
  <p>我是一个段落标签</p>
  <p>我是一个段落标签</p>
  <p>我是一个段落标签</p>
  <p>我是一个段落标签</p>
  <ul>
    <li>无序列表</li>
    <li>无序列表</li>
    <li>无序列表</li>
    <li>无序列表</li>
    <li>无序列表</li>
  </ul>
</body>
</html>